$-9t - 7u + 10v - 10 = 3u - 9v + 6$ Solve for $t$.
Solution: Combine constant terms on the right. $-9t - 7u + 10v - {10} = 3u - 9v + {6}$ $-9t - 7u + 10v = 3u - 9v + {16}$ Combine $v$ terms on the right. $-9t - 7u + {10v} = 3u - {9v} + 16$ $-9t - 7u = 3u - {19v} + 16$ Combine $u$ terms on the right. $-9t - {7u} = {3u} - 19v + 16$ $-9t = {10u} - 19v + 16$ Isolate $t$ $-{9}t = 10u - 19v + 16$ $t = \dfrac{ 10u - 19v + 16 }{ -{9} }$ Swap the signs so the denominator isn't negative. $t = \dfrac{ -{10}u + {19}v - {16} }{ {9} }$